are negligible and estimates for more recent children are lower than those for
children surveyed in the 1980s to the mid-1990s. Of interest, the estimated mean
PALs of contemporary girls and boys 5–12 years fall within the range characteristic
of a sedentary lifestyle (Food and Agriculture Organization 2004 ). Among youth of
adolescent ages, boys tend to have a higher PAL than girls and there is no trend in
PAL across time. In contrast to children, the estimated mean PALs of contemporary
adolescents fall within the range of a moderately active lifestyle.
Estimated PALs of urban and rural children and adolescents in industrial and
developing countries are summarized in Table5.2. Sex differences in PAL within
age and residence groups are not consistent. However, children and adolescents
resident in rural areas of developing countries have, on average, a higher PAL in
each age group than peers in industrial countries and urban areas of developing
countries. With one exception in each sex, mean PALs for girls and boys in
industrial countries and urban areas of developing countries fall within the range of
sedentary and light activity; the mean PALs of late adolescent girls 15–19 years and
boys 10–14 years in industrial countries are at the low end of the range for an active
or moderately active lifestyle (Food and Agriculture Organization 2004 ). In con-
trast, mean PALs of girls and boys in rural areas of developing countries are in the
active or moderately active range during childhood and early adolescence and in the
vigorous or vigorously active range in late adolescents (15–19 years) in both sexes.
Table 5.1 Estimated physical activity levels (PAL) in children and adolescents: 1980s to 2011
Age (years) Girls Boys Source
n PAL n PAL
Children
1980s–mid-1990s 7 – 12 24 1.68 32 1.74 Black et al. ( 1996 )
6 – 13 75 1.80 53 1.79 Torun et al. ( 1996 )a
1996 – 2011 5 – 12 871 1.57 495 1.58 Literatureb
9 – 13 89 1.60 25 1.56 Brooks et al. ( 2004 )
Adolescents
1980s–mid-1990s 13– 17 26 1.73 31 1.75 Black et al. ( 1996 )
14 – 19 34 1.69 37 1.84 Torun et al. ( 1996 )a
1996 – 2011 13 – 18 96 1.71 81 1.79 Literatureb
14 – 18 42 1.69 10 1.80 Brooks et al. ( 2004 )
aMeans are weighted for sample sizes of individual studies, calculated after Torun et al. ( 1996 )
bMeans are weighted for samples sizes of individual studies; references for specific studies are
listed in Appendix 1. In studies comparing obese and non-obese youth or athletes and non-athletes,
only data for the non-obese and non-athletes were used in the compilation. It is possible that some
children are represented on more than one occasion as their data may have been used in several
specific analyses
72 R.M. Malina et al.